Could you please check Administration > Portlet Definitions > Configure Portlet Definitions, in Access tab? (Please check enclosed screen shot) Maybe some configuration could effect on Modul Access grants. If it's work or not work please inform us.
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IT Governance Professional & PPM Solution Architect
in my opinion, if you want to create a module, make it accessible to users and allow the users to change their own preferences, you have to configure the module with Self-Service Access, check "Allow users to add this module to their own Dashboards as Preconfigured Pages" and instruct them on copying.
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